Personal injury law is built on three primary theories: negligence, strict liability, and intentional misconduct. Negligence examines whether the defendant failed to exercise ordinary care, leading to the injury. Strict liability applies when a manufacturer or designer is held responsible for injuries caused by an unreasonably dangerous defective product, even if reasonable care was used in its creation or design. Intentional misconduct includes acts such as battery (harmful or offensive contact), false imprisonment (unlawful detention), and intentional infliction of emotional distress (extreme behavior causing severe emotional harm).